C
amellia Culture
for Home Gardeners
Prepared by James T. Midcap, Extension Horticulturist; Henry Clay, Extension Horticulturist, Retired;
Beverly S. Brewer, Extension Entomologist; and Eugene H. Moody, Sr., Extension Plant Pathologist, Retired
Cooperative Extension Service
The University of Georgia College of Agricultural and Environmental Sciences
CULTURE
Selecting Camellias
Varieties
Select full, well-branched camellias for your landscape.
Look for uniformly shaped plants with vigorous foliage.
Avoid plants with heavy infestations of scale insects on
stems or on the leaf undersurfaces. Avoid plants with
cankers (sunken, discolored areas) on the stems.
Varieties are categorized according to color and hardiness. This list is by no means complete but represents
many of the better varieties for Georgia.
RED
Governor
Mouton* (M)
R. L. Wheeler
Gulio Nuccio*
Professor
Sergeant
Mathotiana
Supreme
Victor
Emanuel*
Lindsay Neill
(M)
Arejishi*
Daikagura* (E)
Tomorrow**
Rutledge
Mimmix* (M)
Flame
Miss
Charleston
Mrs. Charles
Cobb
Firebrand*
Planting Location
Camellias grow best in year-round, semi-shaded areas.
Those planted in full sun are less dormant during winter
warm periods. Sudden temperature drops can cause severe
flower bud and leaf injury. A planting site under tall pines
or on the north side of a building provides more moderate
growing conditions. An open southern exposure is the
least desirable planting site, particularly in the northern
half of Georgia (Figure 1).
Camellias do not tolerate poorly drained soils.
Therefore, do not plant under drain spouts or in depressed
areas where water collects. A gradual decline in plant
vigor is usually associated with root system decline due to
the soil or planting site.
WHITE
Leucantha* (M)
September
Morn (E)
White
Daikagura* (E)
Joshua Youtz
Emmett
Barnes (E)
Alba Plena**
Snowman
White
Empress*
PINK
Marjorie
Magnificent
C.M.
Wilson (M)
Kumasaka*
Dr. Tinsley*
Drama Girl
Berenice
Boddy*
Magnoliaeflora*
(M)
High Hat* (E)
Rev. John G.
Drayton* (L)
Pink
Champagne
Rose Dawn (M)
Lady Clare*
Pink Perfection
Debutante
Mrs. D. W.
Davis
Lady Vansittart
Tiffany
VARIEGATED
Donckelari*
Adolphe
Audusson
Var.*
Ville de
Nantes* (M)
Chandlei
Elegans (M)
Lady Vansittart
Var.
Daikagura* (E)
Herme (M)
R. L. Wheeler
Var.
Gulio Nuccio
Var.*
Tricolor*
Betty Sheffield
Supreme**
Lady Kay
Reg Ragland
Var.
Kumasaka Var.
(L = late, M = mid-season, E = early)
* Varieties that produce cold-hardy flower buds. These varieties grow
well in North Georgia.
** Camellias recommended only for South Georgia because of susceptibility to cold injury.
Planting Time
Plant camellias any time of the year as long as they are
properly planted and tended. Balled-and-burlapped camellias transplant best during the dormant season, which is
fall through spring. Planting dormant plants reduces the
attention required. Soil moisture is usually adequate during the winter and the root system readily grows. When
Figure 1. Moderate shade provides considerable winter
protection to camellias.
1
spring arrives, the plant has a well-established root system
able to support new growth.
Although container plants transplant easier during the
dormant season, they can be planted during the warm
months. Planting container stock minimizes transplanting
shock because no roots are cut. If warm season planting is
necessary, water the plants regularly and thoroughly.
Planting Procedure
When planting two or more camellias in an area, plant
them in a well-prepared bed instead of individual holes.
Cultivate the soil 8 to 10 inches deep to encourage root
growth and establishment.
Camellias are shallow-rooted plants; therefore, good
drainage is essential. When planting on poorly drained
sites, raise the bed 10 to 12 inches above normal soil level.
Use well-drained soil and shape the bed so that excess
water drains out of it.
Plant camellias in holes at least two times wider and no
deeper than the root ball. Remove all cords or wire and
pull the burlap back from the top 8 to 10 inches of the ball.
Place the plant in the hole so that the root ball is level with
the soil surface. Backfill around the root ball with native
soil after breaking apart clods and removing debris. Use
your hand to firm the soil around the roots and then water
to eliminate air pockets. Current research shows organic
amendments are not essential in the planting hole. In fact,
fine-textured amendments, such as peat moss and compost, are detrimental in certain soils.
You can use organic amendments on the soil surface. Place
a 3-inch layer of organic mulch, such as pine straw, pine bark
or well-rotted sawdust, on the soil surface to maintain uniform soil moisture and reduce weeds (Figure 2).
Figure 3. A semi-double variety (left) is not as susceptible to cold injury in the bud stage as a double flowering
variety (right).
There are additional approaches to providing winter protection against plant damage. Maintain good soil moisture,
especially just before freezes. Maintain adequate nutrition
by following current fertilizer recommendations. Plant in
locations that provide moderate winter shade. Select varieties with good winter hardiness (Figure 3.)
Fertilization
Camellias do not require heavy applications of fertilizer.
One level tablespoon per foot of plant height applied in
March, May and July is usually sufficient. Spread the fertilizer evenly on the soil beneath the plant and extend it
several inches beyond the drip line.
Camellia fertilizers are good but a general analysis such
as 8-8-8 or 10-10-10 also gives satisfactory results. Only
two applications (in March and July) are necessary when
using a slow-release fertilizer.
Water in the fertilizer to increase its distribution into the
soil. It is not necessary to remove the mulch before fertilizing if watered afterward.
Watering
Maintain vigorous camellias through proper watering.
Because they have shallow root systems, camellias are susceptible to drought damage. Apply water slowly to get maximum soil penetration. Wet the soil to a depth of 15 to 18
inches. Rewater when the soil in the root zone begins to dry.
Water adequately the first summer after transplanting
but be careful not to over-water camellias. Water once a
week when rain is inadequate. Properly mulch camellias to
conserve moisture.
Figure 2. Plant properly for a healthy beginning.
Winter Protection
Pruning
Covering a camellia plant provides frost protection but
does little good in a severe freeze. If plants are covered
with cloth, plastic or paper, prop up the cover so that it
does not touch the buds. Put the cover on after the sun goes
down and remove it before midmorning the next day.
Homeowners seldom prune their camellias. While little
pruning is necessary for compact-growing camellias, it is
recommended on young plants that are not compact and is
done in late May or early June. Pinch out the tips of vig2
orous shoots to stimulate branching. Remove terminal
buds from vigorous shoots after they emerge in the spring.
This forces the remaining buds into lateral branching,
which helps the plant develop a nice limb structure.
Other pruning is done to control tea scale, which is the
major problem associated with growing camellias. Severe
infestations of tea scale, found on the underside of the
leaves, causes defoliation and loss of plant vigor. Plants then
become unattractive and fail to produce quality blooms.
Remove small nonflowering branches, 2 to 4 inches in
length, growing on major limbs in the interior of the plant
because they are a haven for scale. This reduces future
numbers of scale and increases air circulation, which also
helps prevent tea scale.
Spraying is essential for controlling scale; however,
large overgrown camellias are difficult to spray.
Consequently, homeowners neglect them, and scale
becomes a problem. To combat this, drastically prune back
overgrown plants (Figure 4). This removes the excess
foliage and induces lower growth that is easily sprayed.
Prune overgrown plants in late winter. In southern
Georgia, prune in late February to mid-March. In northern
Georgia, prune in mid- to late March. Cut the plants back
to 12 to 18 inches above ground, removing most limbs and
all foliage. Plants cut back higher (2 to 2½ feet above
ground) usually fail to fill out near the ground and are not
as attractive as those pruned closer to the ground.
Sprouts will emerge from the trunk six to eight weeks
after late winter pruning. These develop into vigorous
shoots reaching 2 to 3 feet tall by midsummer (Figure 5).
New shoots usually are crowded and can be thinned in
early to midsummer to encourage proper branching. Pinch
them off as soon as they become 10 to 12 inches long to
promote additional branching.
Good sanitation is important when you are pruning
camellias. Wash or dip the saw in a mixture of one part
bleach to nine parts water to disinfect the blade
between cuts. Do not lay the saw on the ground
because this can spread harmful organisms to the cut
surface of the plant.
Figure 4. Overgrown camellias can be severely pruned if
done at the proper time.
Figure 5. Camellia growth in late September following
heavy spring pruning
3
DISEASES
When these symptoms appear, the disease is in advanced
stages. Control measures at this time might not be effective.
Prevention is the best approach to control. Buy plants
with white fleshy roots and healthy, vigorous tops (Figure
7). Use proper planting techniques and select a suitable
site as previously described.
The following are brief but informative descriptions of
diseases that commonly occur on camellia. Plants grown
under poor environmental conditions and improper horticultural practices are sensitive to disease infestation.
Root Rots
Several different fungi that infect and kill the fine feeder roots cause these diseases. Root diseases are associated
with plants grown in poorly aerated or poorly drained
soils; however, incidences have been found on plants
grown under optimum conditions.
Flower Blight
The fungus Sclerotinia camelliae Hara causes flower
blight of camellia (Figure 8).
Disease development requires cool, moist conditions in
early spring just before or during early bloom. The disease
first appears as
small, water-soaked
spots or as large, single, brown to tan
areas in the flower
center. During proper weather conditions the smaller
spots rapidly expand
to encompass most
of the bloom. Petals
are quite slimy to the
touch.
Flowers
growing in the shade
Figure 8. Life cycle of the cameloften become severelia flower blight fungus
ly diseased because
of the extended period of time that moisture is on the
leaves. Initially, this disease mimics cold damage; however, cold damaged petals are not slimy.
The fungus carries over to the next season on fallen, diseased blooms. Pick up all infected flowers and discard.
Mulching, as well as spraying with a fungicide, is preventative maintenance.
Figure 6. Note the high percentage of dead feeder roots.
Above-ground symptoms appear as nutrient deficiencies in
leaves, marginal leaf burn, wilting and twig die-back.
Plant response to root diseases resembles symptoms
associated with iron deficiency, sunscald, fertilizer burn or
“wet feet.” Root diseases are progressive. As the fungus
kills more of the feeder roots, you will see extensive plant
wilting, twig die-back, leaf drop, overall plant decline or
death (Figure 6).
Twig Die-back
Another disease, die-back, is sometimes associated
with root rot because it mimics the root rot symptom.
The die-back disease is caused by the fungus Glomerella
cingulata. Infections occur through wounds or natural
openings (leaf and petal scars and lenticels). Initially,
die-back symptoms appear as small, dark sunken areas
(cankers) on twigs and stems. As the canker enlarges,
infected stems become girdled. Stems above this girdling
progressively die causing leaves to wilt. Only individual
twigs or stems are affected at first. Prune infected twigs
and spray the plant with benomyl as the label indicates.
Disinfect pruning shears with 70 percent rubbing alcohol
when making the final cut. Then spray the pruned plant
with fungicide.
Figure 7. Note the white, healthy feeder roots. Above ground,
these plants have vigorous growth and rich, green foliage.
4
Figure 9. Camellia leaf gall causes large, thickened
leaves on the terminal growth. Sasanqua camellias are
more sensitive to this disease than japonica varieties.
Figure 11. The scabby-like projections on the camellia
leaves are characteristic of edema. This condition is a
physiological problem.
Leaf Gall
Sunscald
Leaf gall symptoms are characterized by thickened
and enlarged leaves. To control, simply pick off infected
leaves before they turn white. This practice reduces
inoculum production, which is necessary for disease
development in subsequent years. Sasanqua camellias
are more susceptible to this disease than japonica varieties (Figure 9).
This condition occurs on camellias transplanted from
a shady to a full-sun environment. Areas of the leaf
gradually turn brown. Plants under drought conditions
or having poor root systems express similar symptoms.
Avoid sunscald by establishing camellias in partial
shade and maintaining adequate moisture during dry
periods.
Viruses
Symptoms of
viruses include a
yellow mottling
of the leaves and
color variegation
of the blooms
(Figure 10). Such
symptoms vary
from year to
year. Effects of
the virus appear
to be minor on Figure 10. A yellow mottling of terthe plant. Simple minal leaves is a symptom of a viral
pruning of in- infection.
fected branches 3
or 4 inches below the symptoms is beneficial.
Figure 12. Lichen growth on camellia stems often indicates a poor root environment.
Edema
Lichens
Initially, symptoms appear as water-soaked spots on leaf
undersurfaces but gradually change into brown, corky
swellings. Such tissue is often referred to as excrescence.
This condition appears to be physiological and not pathological (Figure 11). Moisture fluctuations are thought to
cause edema. Poor soil drainage and excessive watering
lead to this problem.
A lichen is a symbiotic relationship between an
alga and a fungus. Extensive lichen colonies on stems
and branches indicate an unthrifty or slow-growing
plant (Figure 12). Lichens are not parasitic and usually do no harm. To control lichens, improve plant
maintenance.
5
Fertilizer Burn
Sooty Mold
Excessive and frequent fertilizer applications often devastate camellias. Too much fertilizer kills feeder roots,
causing symptoms nearly identical to root rot disease.
Initially leaf margins turn brown. If the situation is severe,
entire leaves appear as if they were burned by fire.
Stunting and even death can occur. Avoid over-fertilization by following the recommendations in this publication.
A thin black covering over the upper leaf surfaces characterizes sooty mold. Sooty mold is not a disease but is
associated with insect infestations. Aphids, white flies and
some scale insects secrete honeydew, which drops onto the
leaf surfaces. The sooty mold fungi use honeydew as a
food source. Sooty mold reduces the light intercepted by
the leaf and weakens plants.
INSECTS
Mites
Two broad groups of insects and mites are pests of
camellias. The first group causes damage by sucking juices
from the plant. Scale insects, mealybugs, aphids and mites
are examples of this type of pest. Symptoms include stunted plants, irregular growth, droopiness, discolored foliage
and partial to complete defoliation. The second group causes damage by chewing on the plant. Infestation can cause a
delay in blooming and a ragged appearance. Several weevils, beetles and crickets fall into this category.
Spider mites are small and often difficult to detect on
camellias. Place a piece of white paper or cloth under several leaves then tap the leaves to dislodge the mites. They
can be seen moving around on the white background. Mite
infested plants have foliage that appears dusty. When high
populations of mites are present, you can see webbing on
the surface of leaves.
Bud mites are also camellia pests. They are microscopic
in size and feed at the base of flower buds. Infestation
often results in distorted and poor-quality flowers.
Aphids
These small, soft-bodied insects are often called plant lice
and are usually found along the stems of new growth or the
underside of leaves. Symptoms of infestation include the curling of affected leaves and a sticky residue on the leaf surface.
Beetles and Weevils
The black vine weevil, Fuller rose beetle, Rhadopterus
picipes (cranberry rootworm) and Japanese beetle are insects
that damage camellia leaves. They chew circular or crescentshaped holes in leaves causing the plant to look ragged.
Insect Control
Figure 13. Tea scale is the most severe insect problem
associated with camellias.
Summer oils, or white oil emulsions, control scale
insects, aphids and spider mites by enveloping them in a
film that interferes with their respiration. However, these
sprays can injure plants if temperatures are exceedingly
hot or drop below freezing soon after application. Apply
oil emulsion sprays in the spring and fall. Read the label of
the product for restrictions on timing and application rate.
Systemic insecticides such as dimethoate (Cygon),
acephate (Orthene) or Di-Syston control scale insects,
aphids and several other pests. The plant absorbs these
insecticides, which in turn controls feeding insects.
Contact insecticides include malathion, chlorpyrifos
(Dursban), diazinon and carbaryl (Sevin). They are very
effective and kill insects by direct contact during application or when pests contact a treated plant surface. Because
their residual effectiveness is limited, repeat applications
when pests reappear.
Scale Insects
Scale insects are the most common and troublesome
insects associated with camellias (Figure 13). Examples
include tea scale, greedy scale, peony scale, oleander
scale, wax scale and hemispherical scale. Scales vary in
appearance according to species and sex. Their color
ranges from white (many immature male scales are white)
to brown or black. As scales mature, they develop a hard
outer covering that protects them from contact insecticides, thereby making them difficult to control. Scales are
most often found on the underside of leaves but can also
be attached to stems. Symptoms of infestation include a
yellowing of the upper leaf surface followed by leaf drop
and twig die-back.
6
GRAFTING CAMELLIAS
Figure 16.
Four scions are
grafted onto
this large
understock.
Camellia plants that produce small inferior flowers or
those more susceptible to cold injury can be grafted to correct these conditions.
Grafting unites a vigorous plant’s root system (the
understock) with a branch of the desired variety (the
scion). After the graft takes, the scion grows rapidly. The
cleft type of graft is commonly used with camellias and is
perhaps the easiest of all the grafting methods.
The best time to graft camellias is in late winter, about
four weeks before the foliage begins to grow. This allows
the scion and understock time to unite before temperatures
get high enough to stimulate new growth. February is a
good month for camellia grafting in the Coastal Plain area.
Late February and early March are good times to graft in
the Piedmont area.
The Understock
Use vigorous varieties or seedlings of the japonica or
sasanqua varieties as understock. Prepare the understock
by pulling back the mulch and soil from the base of the
plant. Cut the understock 1 to 2 inches above ground level
(Figure 14). Make a smooth cut with a fine-tooth saw to
prevent bark injury
The understock should be at least ½ inch in diameter.
Grafting on smaller understock makes it more difficult to
get the desired union. If the understock is less than 1½ inches in diameter, split it down the center about 1½ inches. Do
this by tapping the upper surface of a sharp butcher knife
with a hammer or mallet (Figure 15). Keep the blade clean
and do not allow soil to get into the cut area (the cleft).
For understock more than 1½ inches in diameter, do not
cut the cleft through the center of the stock. Instead, make
Figure 17. Nails are used on this large understock to
prevent scion crushing.
the cuts ½ inch from the sides. A cleft in the center of large
stock (more than 2 inches in diameter) puts too much pressure on the scion and forces it out of its proper position or
crushes it. When cutting more than one cleft, make the
cuts parallel (Figure 16). Place a nail in the center of the
understock to reduce the pressure on the scions. Remove
the nail after the graft has taken (Figure 17).
The Scion
Figure 14. Saw the understock carefully so that the
bark remains attached to
the wood.
Take the scion from the dormant terminal growth of the
desired variety. It should be 2 to 3 inches long and should
contain one to three vegetative buds (Figure 18).
Remove all but two or three terminal leaves. Cut the
base of the scion to a wedge-shape. Make the wedge onesided, as shown in Figure 19.
Sharpen your knife just before cutting the scion. A dull
knife invites poor results!
Figure 15. A butcher knife
and hammer are convenient
tools for making a cleft in
the understock.
7
Figure 18. The scion should be 2 to 3 inches long and
contain one to three vegetative buds.
Use this general guide
for the number of scions to
insert per understock:
When the understock is
below ¾ inch in diameter,
use one scion; ¾ inch in
diameter, use one scion; ¾
to 1 inch, use two scions;
1½ to 3 inches, use four
scions; and above 3 inches,
use six scions.
Store scion wood in a
plastic bag and refrigerate
if grafting cannot be done
immediately after the
Figure 19. A side and cross
scions are collected.
section view of a properly cut
Moisten the inside of the
scion. Note that the cuts are
bag before putting the
smooth and even and that the
scion wood in it and seal
base is slightly one-sided.
the bag tightly. The scion
The shading shows the locashould last two to three
tion of the cambium cells.
weeks when refrigerated.
Before inserting the scion, force open the cleft by wedging a screwdriver into the center (Figure 20). Place a scion
on each side of the cleft as illustrated (Figure 21). Do not
allow the cut surface of the scion to dry out before insertion.
Figure 21. Proper alignment of the scion and understock
is essential for successful grafting. The shaded area is
the cambium. Note that the cambium of the understock
contacts with the cambium on one side of the scion.
Figure 22. The understock
and scion must fit together
perfectly for a successful
union.
Figure 20.
Insert a screwdriver as a
wedge to open
the cleft for
inserting the
scions.
Figure 23. Poor fit of the
understock and scion
results in graft failure.
Recut the scion to match
the understock.
Figure 22 shows a good union of the cambium cells of
the scion and understock. The union in Figure 23 will
probably fail because the scion and understock are not in
good contact.
Tie a rubber band around the stock if it is less than ¾
inch in diameter (Figure 24).
Small stocks do not exert enough pressure on the scions
to hold them in place. Remove the rubber bands after the
scions begin to grow.
Next, protect the graft union from moisture loss. A small
handful of damp sphagnum moss tied around the graft
union retains moisture. Grafting wax or static asphalt
8
Figure 24. Note how the
Figure 25. Asphalt tree
ends of the rubber band are wound compound or statsecured without tying.
ic asphalt protects the
cut area.
Figure 26. High humidity is Figure 27. A paper bag is
necessary when the graft
a practical shade cover for
union forms. Covering the
the glass jar. Anchor the
graft with a glass jar causes bag to the ground with soil.
moisture to collect.
Carefully water plants during new scion growth.
Growth of 1 to 2 feet during the first growing season is
common and on a large understock it may reach as much
as 4 feet. When growth is rapid, prevent breakage by
tying it to a stake.
pruning compound painted over the grafted area also holds
moisture in (Figure 25).
Mix 1 teaspoon of captan fungicide with each pint of
asphalt to keep disease out of the cut areas.
Maintaining Humidity
Grafting Large Plants
High humidity around the graft is essential. Maintain
humidity by covering the graft with a wide-mouth gallon jar.
This causes moisture to collect inside the jar. (Figure 26).
Constructing a wire frame and covering it with a clear
polyethylene bag is another way to maintain humidity.
Seal the bag to the ground with soil to hold moisture in.
Another method used is to place a large waxed paper cup
over the graft. Anchor it to the ground with soil to maintain humidity and provide shading. When the new growth
reaches the top of the cup, push out the top to allow the
growth to come through the opening. Waxed paper cups
allow enough sunlight to reach the graft. Do not use ordinary paper cups that will not let light inside.
Do not cut the plant off near ground level if it is
very old. Instead, cut the top back to the lower limb
system. Place a box around the trunk and fill it with
soil or sand. Cut the branches off close to the soil
level and make standard cleft grafts on each branch
(Figure 28).
Figure 28.
Twelve scions
were grafted on
this large
understock in
February. This
photograph was
taken in
October of the
same year.
Shade Cover
Glass jars and clear plastic covers result in a heat
buildup around the plant which can kill the scion
unless some type of shade is provided. Be sure to leave
several inches open to the light on the north (shaded)
side of the cover. Shade transparent covers with a
square piece of burlap or paper grocery bag. Cut a 6inch square window in the bag to let in light on the
north side (Figure 27).
Hardening of Graft
Let air into the graft gradually when the new growth
almost reaches the top of the jar. Tilt the jar or punch holes
in the cup or bag. Then remove the glass or cover and
allow the growth to harden under the shade.
9
Reducing Disease During Grafting
organisms that severely injure the root system. Improve
soil drainage and aeration and reduce the watering frequency to meet the plant’s needs.
Graft failures are often caused by disease entering the
cut surface of the understock or scion. The fungus
Glomerella cingulata, which causes die-back disease, is
the most common disease. It does not enter camellia plants
until there is some type of wound. Consequently, grafting
wounds offer an ideal place for this organism to enter. The
disease is also favored by extremely rapid plant growth;
therefore, growth is quite susceptible to die-back disease.
Several procedures are effective in preventing disease.
Use a fungicidal solution of 50 percent captan or 75 percent ferbam (Fermate) at 2 tablespoons per gallon of
water. Then dip the trimmed scions in this for one to two
minutes. Drench the entire graft area in the solution after
inserting the scion to improve “takes.”
Excess water also affects the vigor of recently grafted
camellias. A common error, especially with containergrown camellias, is keeping the soil too wet before the
graft begins vigorous growth. Insufficient soil drainage
and a reduction in the plant’s water use attract root-rot
Common Causes of Graft Failures
•
•
•
•
•
•
•
•
•
Failure to have close contact between the scion
and understock because of an improperly shaped
scion wedge.
Failure to align the cambium layers between the
scion and understock.
Hitting the scion in the process of covering the
plant, thus changing the alignment.
Poor sanitation which allows disease to enter the
graft union.
Failure to provide high humidity around the graft.
Failure to shade the glass or plastic cover properly.
Suddenly removing the glass or plastic cover
without protecting the tender new growth.
Incompatibility between the scion and the understock.
Unhealthy stock or scion.
GIBBING CAMELLIAS
Camellia flowers are often disappointing when the plant
has sustained winter injury. Hard winter freezes frequently injure Camellia japonica buds before they open. Also,
many varieties flower in midwinter when there is the
greatest danger of cold injury to the open blossoms.
Use a growth regulator, gibberellic acid, to speed up
flower production and obtain blossoms before winter. This
chemical allows many gardeners in North Georgia to grow
flowers on plants that seldom produced good flowers.
Gibberellins are growth-regulating chemicals produced
by most plants in very small quantities. The chemicals are
prepared commercially from the rice fungus Gibberella
fujikuri. The most commonly used gibberellin is gibberellic acid. The process of applying the chemical is often
called “gibbing.”
Gibberellic acid in a water solution is commercially
available. For each flower, apply only one drop of the
solution to stimulate it into production. Note in Figure 29
that the flower bud is plump and rounded while the vegetative bud is smaller and pointed. Begin treatment by
twisting out the vegetative bud that is next to a well-developed flower bud (Figure 30).
This leaves a cup of bud scales at the base. Put a drop of
the solution into this cup (Figure 31).
The chemical will translocate to the flower bud, which
should begin noticeable growth within two weeks (Figure
32).
The time required for treated buds to flower is difficult
to predict because variation occurs among varieties.
Treatments made in September on early flowering vari-
Figure 29. Select a plump flower bud that has a vegetative bud next to it.
Figure 30. Remove the vegetative bud with a twisting
motion.
10
Figure 31. Place only one drop of gibberellic acid in the
vegetative bud cup.
Figure 32. An untreated bud is located on the left. The
center bud was treated 10 days earlier. The bud on the
right was treated 25 days earlier.
eties can bloom within 30 days. Varieties that normally
bloom late often require 60 to 90 days to open.
September and October applications are best. Apply gibberellic acid in early September for late-flowering varieties. On large plants, treat five to 10 buds each week to
obtain flowers over a long period of time.
Prepared gibberellic acid solution is now available at
many Georgia nurseries and garden centers. If unavailable
locally, the American Camellia Society, P. O. Box 212, Fort
Valley, GA 31030, can give you sources for the ready-touse solution. This organization also has a list of sources for
the crystalline material and instructions for preparing it.
Treat a large number of buds on mature camellia plants.
Growers report treating 50 blossoms on large plants for
three consecutive years without injury. However, defoliation and apparent injury were reported when all the buds on
small plants were treated. On small plants only 2 to 3 feet
tall, treat approximately one out of every five to 10 stems.
Terminal vegetative buds on treated stems usually fail to
make normal growth in the spring; therefore, cut treated
flowers for use in the home or prune the stems back later
to the third or fourth vegetative bud.
In addition to early flowering, gibberellic acid treatment
often results in a noticeable increase in flower size and
quality. 5-inch gibbed flowers are not uncommon on some
of the large flowering varieties. Growers find they can produce greenhouse-quality flowers on outdoor plants. Treated
flowers remain on the plant longer than normal. Chemical
treatment is most effective on healthy, vigorous plants.
Response to treatment varies considerably among
camellia varieties. As a general rule, the early and midseason varieties respond much better than late flowering
varieties. A few do not respond by producing earlier flowers and some produce flowers that are quite different in
petal formation from the normal blossoms. Some varieties
have color variation, such as bleaching of the pink varieties and purpling of the normally red varieties.
The following varieties have reportedly responded well
to the treatment:
• Arejishi
• Christine Lee
• Daikagura
• Debutante
• Dr. Tinsley
• Dr. W. G. Lee
• Eugenia Howell
• Flowerwood
• Herme
• High Hat
• Lady Vansittart
• Margaret Hertrich
• Martha Brice
• Mathotiana
• Mathotiana Supreme
• Morning Glow
• Mrs. Charles Cobb Var.
• Mrs. Josephine Hern
• Pink Perfection
• Pink Star
• Rev. John Drayton
• Rosea Superba
• Scented Treasure
• Tiffany
• White Giant
11
ATTENTION: PESTICIDE PRECAUTIONS
1. Observe all directions, restrictions and precautions on pesticide labels. It is dangerous, wasteful
and illegal to do otherwise.
2. Store all pesticides in original containers with
labels intact and behind locked doors.
3. Use pesticides at correct dosage and interval to avoid
illegal residues or injury to plants and animals.
4. Apply pesticides carefully to avoid drift.
5. Use excess pesticides according to label directions.
Follow label instructions for container disposal.
The University of Georgia and Ft. Valley State University, the U.S. Department of Agriculture and counties of the state cooperating.
The Cooperative Extension Service, the University of Georgia College of Agricultural and Environmental Sciences offers educational
programs, assistance and materials to all people without regard to race, color, national origin, age, sex or disability.
An Equal Opportunity Employer/Affirmative Action Organization Committed to a Diverse Work Force
Horticulture
Bulletin 813
Reprinted February 2000
Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, The University of Georgia College of
Agricultural and Environmental Sciences and the U.S. Department of Agriculture cooperating.
Gale A. Buchanan, Dean and Director